Characterization of ESX-1 components EccA1, EspG1 and EspH reveal pivotal role of Esp substrates in the Mycobacterium marinum infection cycle

ABSTRACT: The pathogen Mycobacterium tuberculosis employs a range of ESX-1 substrates to manipulate the host and build a successful infection. Although the importance of ESX-1 secretion in virulence is well established, the characterization of its individual components and the role of individual substrates is far from complete. Here, we describe the functional characterization of the accessory ESX-1 proteins EccA1, EspG1 and EspH, i.e. proteins that are not present in all five ESX system of mycobacteria. Proteomic analysis revealed that EspG1 is crucial for ESX-1 secretion, since all detectable ESX-1 substrates were absent from the cell surface and culture supernatant in an espG1 mutant. Deletion of eccA1 resulted in minor secretion defects, but interestingly, the severity of these secretion defects was dependent on the culture conditions. Finally, espH deletion showed a partial secretion defect, only secretion of EspE, EspF and EsxA/EsxB was blocked.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Mycobacterium Marinum Atcc Baa-535

DISEASE(S): Tuberculosis

SUBMITTER: Sander Piersma  

LAB HEAD: Connie Ramona Jimenez

PROVIDER: PXD008905 | Pride | 2018-08-02

REPOSITORIES: Pride